Earth drilling system



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EARTH DRILLING SYSTEM Filed March 27, 1925 WITNESSES: INVENTOR fll Z ATTORNEY Patented June 12, I934 1,962,346 EARTH DRILLING SYSTEM Frederic W. Hild, Los Angeles, Calif.

Application March 27,

1925, Serial No. 18,789

12 Claims. (01. 25519) My invention relates to systems of motor control and it has particular relation to such systems as are employed in connection with earth-drilling and the like. i

In my copending application, Serial No. 454,451, filed March 22, 1921, (Patent No. 1,808 222 drill, while the other motor performs a regulating function to control the rate at which the drillbit is fed.

The

' when so directed,

invention to provide automatic means, independent of manual control, for maintaining the desired load limit. a

My invention will be best understood by reference to the accompanying drawing in which the single figure is a diagrammatic representation of trolled respectively by switches 6 and 7. Speedregulating means comprising resistors 8 are proor the drilling motor from circuit.

The operating coil 15 of switch 11 is connected to a source of alternating-current ng normal drilling operations, the relative Duri speeds of motors 4 and 5 are adjusted manually speed may,

of course, value so as to retard or stop the rotation of the and relieve the strain on the lling pipe, until the obstruc- When normal drilling I claim as my invention:

1. In a drilling system, in combination, a drill, draw-works for supporting the drill, a rotary table for operating the drill, a motor for operating the rotary table and draw-works, a differential drive interposed between the motor and the operated rotary table and draw-works, an auxiliary motor for operating the rotary table, said auxiliary motor being disposed to cooperate in operating the differential drive and time-limit means controlled by the load on the auxiliary motor for dividing the rotary-table load between the motors to meet operating conditions.

2. In a drilling system, in combination, a drill, a draw-works for supporting the drill, a rotary table for actuating the, drill to perform drilling operations, a motor for actuating the rotary table and draw-works, means for dividing the torque delivered by the motor between the rotary table and draw-works, an auxiliary motor disposed to cooperate in operating the rotary table and timelimit means controlled by the load on the auxiliary motor for dividing the rotary-table load between the motors as the weight of the drill on the draw-works varies.

3. In an earth-boring system, in combination, a drill, means for suspending the drill in a position to perform working operations, means for rotating the suspended drill to perform the drilling operations, a motor for actuating the drillsuspending means and the drill-rotating means, an auxiliary motor disposed to cooperate in actuating the drill-rotating means and time-limit means controlled by the load of the auxiliary motor for dividing the drilling load between the motors in a predetermined ratio.

4. The combination with a rotary drilling machine comprising a drilling tool and a driving motor therefor, of a second motor for controlling the tool, a differential mechanism controlled by to movements of a planetary member of said mechanism for. effooting feeding movements of said tool, manually operable means for adjusting the speed of said second motor to control the tool-feeding and current responsive means dependent upon the load of the driving motor and time-limit means controlled by the current-limit means for further controlling the speed of said second motor independently of said manually operable means.

5. A transmission mechanism comprising a driven member, a feed mechanism for the driven member, two motors for driving the driven memher, a source of electrical energy for the motors, a differential mechanism for transmitting power from the two motors to the driven member and for communicating the torque of one motor to the feed mechanism and time-limit means for regulating the proportion of the torque supplied by each of the motors by controlling the supply of current to them and means responsive to the load of one motor tocontrol the time-limit means.

6. In an earth-boring system, in combination, a boring device, control mechanism for operating and controlling the operation of said boring device, a plurality of motors for operating said control mechanism, a source of electrical energy for the motors, a differential gear m said motors being coupled to the control mechanism through the differential gear mechanism, and means for automatically controlling th supply ofcurrenttooneofthemotorstovarytheirrelative torques in accordance with the resistance encountered to the actuation of the boring device.

I. In an -bor2ng system. a drill disposed anism, comprising three to operate under a feeding pressure resultin from the action of gravity upon it, a hoisting mechanism connected to the drill, a motor for operating the drill, means for transmitting power from the motor to the drill and for exerting the torque of the motor upon the hoisting mechanism to exert a force upon the drill in opposition to the force exerted by gravity to obtain a uniform feeding pressure, a second motor operatively connected to the drill for ass ting the first motor, and time-limit means controlled by the load on the motor operating the drill for varying the proportion of the total power exerted by each motor to change the uniform feeding pressure.

8. In an earth-boring system, in combination, a drilling element comprising a drill bit and a relatively heavy drill stem for rotating the drill bit, said drill stem being disposed in such manner that its weight tends to force the drill bit downwardly, a motor for driving the drilling element, a feeding mechanism for exerting a force on the drilling element in the upward direction, a differential mechanism for transmitting power from the motor to the drilling element to rotate it and for exerting torque to operate the feeding mechanism whereby the force exerted by the feeding mechanism is in direct proportion to the torque exerted by the motor, a second motor operatively connected to the drilling element for assisting the first motor, time-limit means operable after the lapse of a de 'te time for regulating the proportion of the total torque exerted by each motor to adjust the feeding pressure and means responsive to the load of said second motor for controlling said time-limit means. v

9. A boring mechanism, comprising a driven element, a feed mechanism for the driven element, two motors for driving the driven element, a source of electrical energy for the motors, a differential mechanism interposed between one of the motors and the driven element through which substantially all of the power of said motor is transmitted to the driven element and the reaction torque thereof is utilized to operate the feed mechanism and means for automatically varying the ratio of current input to the two motors to thereby regulate the torque exerted by one of the motors upon the feed mechanism to change the boring pressure.

10. In an earth-boring system, in combination, a driven element, an electrical motor for driving said element, a source of electrical energy for said motor, a feed mechanism for the driven element, a differential mechanism interposed between the motor and the driven element and operatively connected to the feed mechanism whereby the power of the motor is transmitted to the driven element and the reaction torque of the differential mechanism is utilized to operate the feed mechanism, a second electrical motor connected between the diflerential mechanism and the driven element for assisting the first motor and means for automatically varying the ratio of the current supplied to the two motors to regulate the torque of the first motor and consequently the torque exerted upon the of regulating the feeding pressure in such manner that the total torque applied to the driven element will be maintained substantially constant.

11. In an earth-boring system. the combination with a drilling mechanism, of a differential mechelements for transmitting power to the drilling two electrical motors for driving the drilling mechanismone of said motors being connected to one eleent of the diiferential mechanism and the other regulate the ratio of the torque applied to the feed mechanism to the drilling mechanism.

torque applied to the 12. In a drilling system, in combination, a drill, a motor for operating the drill, means for exerting a force tending to feed the drill towards the material being drilled, a retracting mechanism for exerting a force in opposition to the feeding force, a differential mechanism for transmitting power from the motor to the drill and for exerting torque-to operate the retracting mechanism whereby the force exerted by the retracting mechanism is in direct proportion to the torque exerted by the motor and, consequently the drilling pressure is inversely proportional to the drilling torque, and a second motor cperatively connected to the drill and means whereby the inverse relation of the drilling pressure to the drilling torque may be automatically regulated by adjusting the ratio of the torques exerted by the two motors.

FREDERIC w. 'HILD. 

